Porous carbon materials are used in numerous applications, including for separation, catalysis, and energy storage (e.g., battery components). The synthesis typically involves the carbonization of either synthetic or natural polymer sources. Polymer carbon precursors have been favored primarily because of their low vapor pressures. The low vapor pressure of polymers results in high char formation along with a virtual absence in vaporization during carbonization.
However, the use of polymers in the carbonization process has several drawbacks. At least one significant problem in using polymers is their high viscosity, which makes polymers difficult to apply as a coating on a substrate in the production of carbon films. Often, the polymer is a solid. Accordingly, the highly viscous or solid polymer typically requires dissolution in a solvent in order to apply the polymer as a thin film on a substrate. However, in order for the carbonization process to produce a seamless continuous carbon film, a preceding solvent removal step (i.e., calcination) is required. Not only is the calcination step time-intensive, but the calcination step can, itself, introduce imperfections into the final carbon film.
Attempts have been made to circumvent the use of polymers by instead using non-polymer liquid molecules. Non-polymer liquid molecules can be applied in a facile manner as a coating on a substrate. However, non-polymer molecules have thus far been highly problematic mainly because of their high volatility, which results in low or no carbon yields.